


compatible

by marzipan (orphan_account)



Category: Sherlock (TV)
Genre: M/M, Novelist AU, serial killer au, this is just crack again
Language: English
Status: Completed
Published: 2018-10-25
Updated: 2018-10-25
Packaged: 2019-08-07 11:24:56
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,235
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16407584
Author URL: https://archiveofourown.org/users/orphan_account/pseuds/marzipan
Summary: A dating app that matches people based on web preferences and browsing history pairs up Sebastian Moran and Mycroft Holmes. One’s a serial killer, and the other is a murder mystery novelist.





	compatible

**Author's Note:**

> a bit rushed, but WHATEVER, HERE YOU GO

The meat grinder is new.

 

It’s new and shiny and not at all like the trusty one he had back at the warehouse (until Jim blew it up), and that, Sebastian Moran attributes, is why it sticks when the skull finally hits the bottom of the funnel.

 

But it’s only due to that momentary sticking that Sebastian hears the ping on his phone. 

 

He fishes it out of his pocket, remembering to peel off the bloodied glove just in time.

 

_ YOU’VE BEEN MATCHED! ♥ _

 

Sebastian can’t help the slightest twitch of his lips, a blink-and-miss-it smile that doesn’t quite make it up to his eyes. He’s been told he has especially inexpressive eyes. He’s been told he’s especially inexpressive, period. He’s been told by his last, oh, five or so dates.

 

But this app - this app promises to, with the help of a personality quiz and some preferences, pair you up with a person you can really get along with. It hasn’t been out on the market for too long, so Sebastian can’t put much stock in the statistics that promise long term relationships and whatnot, but. He’s tired of dating for the sake of dating. He’s not good at dating. He kind of just want to find someone to be with. With shared interests and all that.

 

He unlocks his screen and swipes open the app to look at the profile of the man he’s been matched with, flipping through the pictures. Glasses, no glasses, oh he looked  _ interesting _ with a beard. Why was he holding an umbrella in half his photos?

 

_ Mycroft Holmes, writer _

 

Sebastian scratched his nose with his thumb as he contemplated messaging the man, then scrolled through the rest of the profile. 

 

_ Wrrrrrrrr. _

 

He looked up at the meat grinder, which’d started grinding just fine again, flesh and bone and cartilage and all coming out into a nice paste out the other end as the man’s right foot disappeared from view into the machine. 

 

Yeah, yeah it’d be nice to have someone to talk to, after a busy week like this. The lost of his favorite warehouse, some of his most trusted tools. Now he was practically painting the town red each night, trying to find another haunt.

 

_ Mrow! _

 

And then there was Kitty, a black and gray striped stray who’d thankfully not been in the vicinity of the explosion. She’d followed him from the last warehouse.

 

Sebastian almost smiled, and tapped out a message to this  _ Mycroft Holmes _ .

 

“Did you bring your friends?” he asked the cat. “This guy’s a big one.”

 

_ Mrow! _

 

.

 

“So, hypothetically, if you were going to kill someone, how would you do it?”

 

Sebastian stares down his date, this  _ Mycroft Holmes _ , who (and Sebastian’s very happy about this) decided to come to this first coffee date wearing his glasses.

 

Sebastian would frown, if he was the expressive type. But he’s not, so he just looks back at his date impassively, chewing on a scone. 

 

He swallows the mouthful of scone.

 

“Blow to the head,” Sebastian says. Honestly, he usually just shoots them. 

 

Though really, how you killed someone wasn’t nearly as important as how you planned to get away with it. Sebastian had perfected the art of getting away with it, and if this guy was a detective or whatever, he wasn’t getting zilch here.

 

Mycroft considers it.

 

“I’d stab him, I think,” he says, setting down his cappuccino. “Something thin enough that the initial blow wouldn’t even register as a wound - but damaging enough to prove fatal later.”

 

Sebastian blinks, a little spark of something fizzing in his chest. He nods, warming up to the idea.

 

“Creative, but the kill’s nothing if you haven’t got a method of disposal, or of getting away, in this case.”

 

“Oh, of course. I’d do it in a crowd, or at least in public. A busy crosswalk, something like that.”

 

The corner of Sebastian’s lip twitches, and he warms his hands around his coffee. 

 

Suddenly, Mycroft looks flustered. He takes a sip of his coffee and sets it back down.

 

“Oh! And before you go thinking I’m a serial killer or anything like that - “

 

Sebastian raises an eyebrow just a hair.

 

“- I’m a novelist.”

 

“Yeah?”

 

“Murder mysteries.”

 

His eyebrow rises just the slightest bit higher.

 

“The, ah, Ministry Murder series.”

 

Sebastian spits out his coffee.

 

“YOu’re Mike Hall?”

 

Mycroft looks sheepish. Sebastian wants to ask him for a second date immediately based on this new factoid alone, as if he hadn’t his heart stolen the moment Mycroft asked his opening question.

 

“I love those books,” he says, expression conveying none of his heartfelt sentiment. Fourteen novels and they still hadn't caught the killer. It was a breathtakingly fresh approach to the genre.

 

“Oh God.” Mycroft is blushing. “You don’t have to say that.”

 

“Don’t have to say that? You’re an inspiration!”

 

It’s true - Sebastian isn’t usually one for flattery, but he pre-orders every book and devours them the very day he gets them, they’re so good. He tells Mycroft as much, regaling him with how he’d dropped one in the bath and the hour he spent drying the pages so he’d be able to turn them without ripping had been just  _ agonizing _ , even more than that time he’d broken his leg and required bed rest. 

 

Mycroft coughs and sputters and laughs at Sebastian’s deadpan retelling, and, Jesus, he had no idea his favorite author was  _ adorable _ .

 

He thinks he’s a little bit in love.

 

.

 

They trade numbers and end up in a cozy bistro for lunch the next day, discussing the mechanics of draining an adult body dry. 

 

Sometime between the sandwiches and the calculations, Sebastian finds Mycroft’s feet tangled between his and they’ve sort of scooted their chairs to be right beside each others and scraped the food to one side of the plate and borrowed the next table’s ketchup so as to mock up a crime scene.

 

.

 

“And that's how they all die,” Mycroft says proudly, the two of them looking down over a rail yard that was to be featured in an upcoming novel. Sebastian hangs on to his every word. 

 

.

 

On Wednesday, Mycroft invites him to a double feature where they’re showing old black and white horror movies and it’s awfully campy but Mycroft looks like he’s enjoying every second, giving practically a commentary track on the films as they sit amongst snogging teens and film students and snoozing seniors. 

 

Sebastian spends a good deal of time watching Mycroft, instead of the screen. But by the time they get to the second film, he sees the appeal, he really does. He makes Mycroft snort with laughter when he describes in detail how each of them would realistically die at the hands of this unknown killer chasing them down.

 

.

 

“You’re dating MYCROFT HOLMES?”

 

Jim Moriarty practically kicks down the door, which, all things considered, actually isn’t very unusual.

 

Sebastian turns to look at him.

 

“Are you going through my phone again? Don’t delete any of my music this time.” 

 

Sebastian understands the concept of privacy, but really he could care less about whether Jim sees the contents of his phone. He just doesn’t like it when the bastard rearranges his apps, or his playlist.

 

“He’s  _ Sherlock Holmes’s brother _ ,” Jim hisses.

 

Sebastian shrugs. They hadn’t gotten to the talking-about-family part. Or exes. He’s not sure who Jim is referring to.

 

“Break up with him,” Jim switches to a whine, complete with a foot-stomp.

 

Sebastian really glares this time.

 

“No.”

 

Jim gives him a look as if he’d suggested they eat the sofa for dinner today.

 

“You need to break up with him! Hello? Sherlock Holmes, consulting detective extraordinaire? My nemesis??”

 

Huh. Looks like crime-adjacent activities ran in the family. Sebastian likes him all the more for it.

 

“I’m not breaking up with him, I think I’m in love with him,” Sebastian explains in measured tones.

 

“You - in  _ love? _ ” Jim stares, aghast, before bursting into laughter so hard he sways and clings to the wall for support. “That’s a good one.”

 

“It is. He is. I’m keeping him.”

 

“Please. You’ll get bored in a week or two and you’ll kill him too.”

 

Sebastian frowns, facial muscles moving of their own volition.

 

“I won’t.”

 

“Yes, you will.”

 

“I’m not discussing this with you,” Sebastian says, crossing the room to disappear down the hall.

 

“When have I EVER been wrong about ANYTHING?” Jim calls after him.

 

.

 

Sebastian met Jim four years ago, a hired gun on a one-off job until Jim offered to employ him on retainer.

 

He liked Jim; the man was practical and entertaining in his own way and let Sebastian do what he did best, no questions asked.

 

It wasn’t until six months into the partnership that Jim discovered his secret.

 

Sebastian had been tailing a chemist for nearly three weeks now, a quirky guy who no one would particularly miss as a person but would likely cause a bit of a panic work-wise, seeing as he and his colleagues were co-authoring a study that was nearly ready for submission. 

 

Thing was, there was something about the way he walked that caught Sebastian’s eye, and the pattern ate at him every time he crossed this university plaza for lunch while he’d been casing the next building over for a separate job.

 

So he figured out the best route, abducted the man, and now he was going to put him through the grinder. 

 

“Who the FUCK is that?” Jim demanded, flinging open a door Sebastian could’ve sworn was bolted.

 

Sebastian looked down at the bloodied face.

 

“Phil or something, I think,” he said. He was already regretting having to shoot Jim next. Jim was a steady paycheck, and normally didn’t ask too many questions. He’d likely not find that elsewhere.

 

Jim stalked over.

 

“I didn’t  _ ask _ you to put out a hit on a  _ Phil _ ,” he hissed, getting a better look at the corpse. “Who are you working for? Are you fucking two timing me?”

 

Sebastian blinked, and scratched his nose. Then he flipped on the meat grinder machine.

 

“No he’s.” He thinks. He hasn’t really had to explain it before. “A hobby?”

 

No, that’s not it.

 

“It’s like an itch,” he tries again.

 

Jim is staring at him, incredulous, and the moment stretches on while Sebastian mentally debates throwing Jim into the grinder first, before Phil. 

 

“So you’re just. Killing people? For f-”

 

“Fun? Kind of.”

 

“I was going to say  _ free _ , but alright.”

 

Sebastian blinked.

 

“Alright?”

 

“Yeah, alright. So long as it doesn’t affect your work. And try to keep it under wraps, alright?”

 

Sebastian would roll his eyes, if he were the expressive type.  _ Keep it under wraps _ . Like he hasn’t been doing this for over a dozen years before Jim came along.

 

.

 

Sebastian stares down at his phone in horror.

 

_ Raincheck tonight? _

 

This is quite possibly, he feels, the worst news he has ever gotten. In his entire life. 

 

_ What's wrong?, _ he texts back in a hurry. Jim couldn't possibly have gotten to him already. Sebastian knew he wasn't above sending a warning though. He'd crush his skull with a door, if he found that to be the case.

 

_ Just _

_ Feeling a bit under the weather. _

_ Really sorry. Dinner Saturday? I'll cook. _

 

Sebastian would have given his phone a forlorn look, if he was the type of person whose facial muscles had a penchant for reflecting his emotions in a dramatic manner. But he's not, so he texts Mycroft in agreement, and wishes him better health. Then sets in for a quiet night in.

 

.

 

Sebastian knocks on the dark wood door, takeaway bags in hand, and waits.

 

“Coming!” There's a crash and a muffled shout, and then the door finally opens.

 

Mycroft’s there, standing in very warm clothes, and his glasses, with a very fluffy cat giving Sebastian a snooty look by his feet.

 

“Sebastian.” Mycroft looks startled. And tired. His eyes are a bit red.

 

Sebastian holds up the bags.

 

“I brought soup.”

 

Mycroft’s whole face turns red, and he opens the door wider so as to let him in.

 

.

 

It turns out Mycroft's not sick so much as wallowing in his editor's notes.

 

“They hate it,” he moans, curled up on the couch beside Sebastian, face buried in his hands.

 

Sebastian frowns. “They're idiots.”

 

“That's very nice of you to say, but my agent and my editor have been with me for a decade and I'm sure they've got some idea of how this works by now,” Mycroft adds miserably.

 

Sebastian puts his arm around him, opens his mouth, then hesitates.

 

“Maybe…” This was the most difficult thing he had ever done in his life. He's not sure he'd be able to cope with the rejection if it comes. “Maybe I could take a look?”

 

Sebastian braces himself, then peeks over at Mycroft.

 

He doesn't expect to find that hopeful, excited expression on his face.

 

“Would you?” Mycroft asks.

 

Sebastian gulps.

 

.

 

Every cell of his body is vibrating with excitement as he holds his hands out, ready to accept the early manuscript of the unpublished next installment of Murders.

 

He takes a deep breath, and then turns the page.

 

.

 

“That was brilliant, bloody brilliant,” Sebastian breathes.

 

Mycroft shakes his head, reaching across him to flip to the middle.

 

“But the beheading in chapter five, see? My editor says this part isn't realistic.”

 

Sebastian frowns, pulls the page back to reread it. Ah.

 

“The choice of weapon?”

 

“You think so too.” Mycroft bites his lip. “The whole chapter hinges on it. I'll have to throw out the entire plot point.”

 

No, no, this wouldn't do.

 

Sebastian steels his resolve. He knew what he needed to do.

 

Leaning down, he picked up his leather jacket as he kissed Mycroft on the top of his head.

 

“I have to go.”

 

.

 

“Mike. Hey.” Sebastian sounds breathless. It’s 3 a.m. Mycroft squints into the darkness of his bedroom.

 

“Sebastian.” It’s half question, half greeting.

 

“It’ll work if he’s been half-frozen.”

 

“What?”

 

“Chapter five. He drags the body to the car park then down the freight elevator to store it, and comes back to finish the disposal.”

 

“Mmhm?”

 

“So say there’s a freezer down there. They cater. I don’t know, you’re the writer, you figure it out. But then your story still works, the weapon doesn’t have to change a bit neither, and the reveal works the same. All that’s got to change is the room the body’s left in has got to be a few degrees colder.”

 

Mycroft blinks rapidly into wakefulness.

 

“How-”

 

“I, uh. I’ve got a friend, a butcher. Asked him to run a little experiment for me.”

 

Mycroft yawns, interrupting a smile.

 

“You’re the best.”

 

Sebastian doesn’t say anything, but Mycroft thinks that sounds like a smile too.

 

.

 

Mycroft and Sebastian are sitting in a cozy tavern when the bar television gets switched to the news.

 

“-a lawsuit against Appledore for infringing on citizens’ privacy. According to these emails, obtained by the Wall Street Journal, the popular dating app which has seen 30 million downloads in just its first month online, knows a lot more about you than you think.”

 

Sebastian steals a kiss, and marvels at how natural displays of affection have become. He’s not smiling, per se, but it feels like he is, and Mycroft smiles back.

 

“The app instructions and introduction copy claim to match people based on the personality quiz you take when you sign up, but according to these patents and memos strongly suggest the app is able to read other data on your device, including your internet browsing history - including any information you’ve input in your browsers, like credit cards-”

 

Mycroft pulls away, pausing to watch the news. 

 

“Well, that’s curious,” he says.

 

Sebastian frowns, mentally. 

 

“Could care less, really,” he says. 

 

Mycroft gives him a funny look.

 

“You don’t care about privacy?”

 

“Not if all they’re going to use my data for is to try to sell me aftershave. You wouldn’t believe the number of shaving ads I’ve been seeing lately,” he says. He supposes it could have something to do with his recent purchase of an antique straight razor that may or may not have been used by a serial killer, but.

 

Mycroft reaches out to run his thumb over Sebastian’s stubble-y jawline.

 

“Plus, it helped me find you, didn’t it?”

 

Mycroft stays his hand, eyes going soft for a moment.

 

Then he clears his throat, pulling back.

 

“I guess that explains why all of my talk of murders and bodies didn’t scare you off,” Mycroft says with a nervous laugh. 

 

Mycroft takes a drink, then looks over at Sebastian.

 

“I never asked,” he says, and Sebastian knows the storm’s coming. “What do you do?”

 

His throat goes dry, and if he were the kind of person whose physiology tended to give him away, his palms might have gotten sweaty.

 

“It’s, um.” His mind reels. “It’s embarrassing.”

 

Mycroft smiles encouragingly, and well, that covered why he never talked about his job, but not what it was he did that had him googling the best ways to drain a body dry, or if it was okay to feed cats human innards. 

 

But. 

 

Perhaps Mycroft would understand?

 

He understood Sebastian so well already.

 

It wasn’t like he didn’t want to talk about what he did, he  _ did _ . And so far it had been good, bringing up his jobs as hypotheticals, letting Mycroft fill in the blanks with his genius-level imagination as if they were little brain puzzles to get him warmed up for his book.

 

Would it really be that bad?

 

“I-”

 

Before Sebastian can say anything damning, a third body slides into their booth. It’s Jim, wearing an ugly Christmas jumper and smiling like the benevolent dictator he was.

 

“He’s an assistant,” Jim says sweetly.

 

“I’m sorry, and you are?” Mycroft bristles.

 

“James Brook, at your service,” Jim says, because he’s a lying liar, and if Sebastian was the expressive type he’d be be shooting him daggers and giving him an expression that said  _ walk away now, or I’ll kill you _ .

 

Mycroft balks, but extends his hand to take his.

 

“I’m sorry, you’re not…?” 

 

“Redriver Castle, yes. The showrunner,” Jim says. “Sebastian here’s my personal assistant, googling corpse factoids and anatomy trivia on his lunch break while getting my coffees, all that jazz. Has this really never come up? And honey, what are you doing here? Don’t you have scripts to highlight?”

 

Sebastian grits his teeth.

 

“You gave me the day off,” he says.

 

Jim pretends to think it over.

 

“Did I?” 

 

Mycroft interrupts. “I’m a huge fan of your work.”

 

“Thank you!” Jim says in the gratified tone of someone who had never once ever been complimented on his accomplishments in the whole of that day. He turns to give Sebastian a look. “See, at least someone appreciates my genius.”

 

Mycroft clears his throat.

 

“Actually, Sebastian here has a fantastic eye for murders,” Mycroft says, and Jim nearly chokes to keep down his laughter. “He’s been invaluable with the editing of my latest book. You’ve a really talented assistant, you know.”

 

Sebastian can feel something chill in the air.

 

Jim sobers, giving Mycroft a curious look.

 

“Really,” he says, not actually a question.

 

“Yes,” Mycroft responds, placing a hand on Sebastian’s arm.

 

He kind of wants to preen, but he’s not the type. 

 

All in all, it’s not that bad of a problem to have.


End file.
